// run

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Test interface assignment.

package main

type Iputs interface {
	puts(s string) string
}

// ---------

type Print struct {
	whoami int
	put    Iputs
}

func (p *Print) dop() string {
	r := " print " + string(p.whoami+'0')
	return r + p.put.puts("abc")
}

// ---------

type Bio struct {
	whoami int
	put    Iputs
}

func (b *Bio) puts(s string) string {
	r := " bio " + string(b.whoami+'0')
	return r + b.put.puts(s)
}

// ---------

type File struct {
	whoami int
	put    Iputs
}

func (f *File) puts(s string) string {
	return " file " + string(f.whoami+'0') + " -- " + s
}

func main() {
	p := new(Print)
	b := new(Bio)
	f := new(File)

	p.whoami = 1
	p.put = b

	b.whoami = 2
	b.put = f

	f.whoami = 3

	r := p.dop()
	expected := " print 1 bio 2 file 3 -- abc"
	if r != expected {
		panic(r + " != " + expected)
	}
}
